Pests (invertebrates, insects, arachnids, larvae thereof, etc.) are annoying to humans for a myriad of reasons. They have annually cost humans billions of dollars in crop losses and in the expense of keeping them under control. For example, the losses caused by pests in agricultural environments include decreased crop yield, reduced crop quality, and increased harvesting costs.
Over the years, synthetic chemical pesticides have provided an effective means of pest control. For example, one approach teaches the use of complex, organic insecticides, such as disclosed in U.S. Pat. Nos. 4,376,784 and 4,308,279. Other approaches employ absorbent organic polymers for widespread dehydration of the insects. See, U.S. Pat. Nos. 4,985,251; 4,983,390; 4,818,534; and 4,983,389. Use of inorganic salts as components of pesticides has also been tried, as disclosed in U.S. Pat. Nos. 2,423,284 and 4,948,013, European Patent Application No. 462 347, Chemical Abstracts 119(5):43357q (1993) and Farm Chemicals Handbook, page c102 (1987).
However, it has become increasingly apparent that the widespread use of synthetic chemical pesticides has caused detrimental environmental effects that are harmful to humans and other animals. For instance, the public has become concerned about the amount of residual chemicals that persist in food, ground water and the environment, and that are toxic, carcinogenic or otherwise incompatible to humans, domestic animals and/or fish. Moreover, some target pests have even shown an ability to develop immunity to many commonly used synthetic chemical pesticides. In recent times, regulatory guidelines have encouraged a search for potentially less dangerous pesticidal compositions via stringent restrictions on the use of certain synthetic pesticides. As a result, elimination of effective pesticides from the market has limited economical and effective options for controlling pests. As an alternative, botanical pesticides are of great interest because they are natural pesticides, i.e.; toxicants derived from plants that are safe to humans and the environment.
The problem is even more evident with respect to the treatment of human body louse, where the treatment of children and other humans demand certain safety attributes. Each year over 10 million Americans get head lice (pediculosis) alone. Head lice are spread through direct contact or the sharing of certain household items and clothing. Many health professionals and parents are very concerned about the toxicity of pesticide shampoos, especially those containing Lindane. Furthermore, recent research indicates that head lice are becoming resistant to permethrin or pyrethrin shampoos, two current treatments for the problem.
Accordingly, there is a great need for novel and effective pesticidal compositions, containing no synthetic pyrethroids, chlorinated hydrocarbons, organophosphates, carbamates and the like, to be used against human body louse. In addition, there is a need for a method of treating the skin and hair, etc. of humans to kill and repel human body louse.